Door lock cylinders are the cylindrical tumblers that are used to lock and unlock the vehicle’s doors. They are installed in the front doors of a vehicle and are matched with a key that will lock and unlock them so that the doors can be opened. While many newer vehicles are now being built without door lock cylinders, they are still commonly found on many road going vehicles. When the door lock cylinders wear out, they can cause problems with locking and unlocking the doors. Usually, a bad or failing door lock cylinder will produce a few symptoms that can alert the driver of a potential problem.
1. Key will not lock or unlock the vehicle
One of the most common symptoms of a problem with the door lock cylinder is a key that will not lock or unlock the vehicle. The key and ignition cylinder are matched to work together as a pair, and if either of them wears out, it may cause issues locking and unlocking the door. A worn door lock cylinder may still unlock the door, but may require excessive turning force or effort to function. The problem will continue to get worse until the cylinder can no longer open the door.
2. Key will not turn in the lock
Another symptom of a problem with the door lock cylinder is a key that will not turn in the lock. If the teeth inside of the door lock cylinder wear out, they may not be able to properly accept the key, and as a result, may not turn in the cylinder. Removing and reinserting may get the door to unlock, however, the problem will worsen until the the cylinder will not unlock at all.
3. Key gets stuck in the lock
A key that gets stuck in the door lock cylinder is another symptom of a potential problem with the door lock cylinder. If the cylinder or key wear or break, it may cause the key to jam or get stuck when inserted in the cylinder. A sticking key can be an inconvenience to the driver, as it will have to be worked back and forth so that it can be removed.
While they are starting to be used less and less as power door locks become standard, door lock cylinders are still commonly found on many road going cars and trucks. For vehicles equipped with them, they are an important component as they are what lock and unlock the vehicle's doors. If you suspect that your door lock cylinders may be worn or having an issue, have the vehicle inspected by a professional technician, such as one from YourMechanic, to determine if you vehicle needs a door lock cylinder replacement, or if another repair should be made.
This article originally appeared on YourMechanic.com as Symptoms of a Bad or Failing Door Lock Cylinder and was authored by Ed Ruelas.